This invention relates to lighting systems, and more particularly, to lighting systems for appliance products, such as, for example, vacuum cleaners, stoves, refrigerators, microwaves, toasters, coffee makers, bread makers, other kitchen and household appliances, and other similar and various other related devices.
Most prior art lighting systems used in appliances employ incandescent bulbs, which have many design disadvantages when trying to place them in small enclosures due to their relatively large size, short usage life and high heat generation. There is a need for a lighting system that uses a small bulb, such as an LED, which has a long life, does not have high heat generation, and can project sufficient light across the expanse of the area desired to be illuminated.
Replacing incandescent bulbs with LEDs would overcome most of the problems of using incandescent bulbs in small enclosures, but LEDs generally produce a small cone of light which typically does not generate adequate illumination to satisfy the majority of lighting requirements in appliances. One of the features of the present invention is to combine one or more LEDs with a specially designed prism to produce a uniform distribution of light of sufficient intensity across a relatively large surface area.
Another feature of the present invention is to use two LEDs in combination with a specially designed prism to further increase the area of illumination. This feature is accomplished in a simple but unique manner by adding a mirror image of the original prism.
An additional feature of the present invention is to utilize a unique complex lens to focus an LED""s beam of light in a manner that keeps the light focused down the length of the prism to reduce the amount of light that bounces or reflects off of the prism""s two parallel plate surfaces. A further feature is to include in the complex lens a spherical end portion that redirects light onto a curved surface of the prism that reflects the light to a light exiting surface of the prism.
According to another feature of the present invention, all of the above mentioned features are incorporated in a plastic prism that can be readily molded to provide an economical alternative to prior known lighting systems, such as those using incandescent light bulbs. The inventive lighting system requires a small amount of power to operate, provides a low operational temperature, is reliable and durable, and vibration resistant. The inventive lighting system can be retrofitted for existing appliance models.
According to the principles of the present invention, by using the unique combination of LEDs with the novel prism designs, lighting colors and lighting patterns can be tailored for desired appearance.
Other features and advantages of the invention will become apparent to those skilled in the art upon review of the following detailed description, claims and drawings in which like numerals are used to designate like features.